1. Field of the Invention
The present disclosure relates to a capacitance estimation apparatus, and more particularly, to an apparatus for estimating a capacitance of a DC-link capacitor used in an inverter.
2. Description of the Related Art
Multi-level medium voltage inverter is an inverter with a line-to-line RMS voltage of greater than 600 V, which outputs a multi-level output phase voltage. The medium voltage inverter may used to drive a high capacity electromotor having a capacitance of several hundreds of kW to several tens of MW, and mainly used in the field of fans, pumps, compressors, tractions, hoists, conveyors, or the like.
Among the multi-level medium voltage inverters, series H-bridge inverters can be easily extended due to their modular structure, and thus mainly used for a medium voltage inverter. The series H-bridge inverter includes a high capacitance DC-link capacitor, but the DC-link capacitor has a problem of most likely causing a fault state.